Breeding birds in the proposed Hitra II power-plant area

2.3.1.1 Methods

Standard line-transect methods (Rosenstock et al. 2002, Burnham et al. 1980, Buckland et al.

1993) were used in the plan area. 12 transects were defined in an east-west orientation, each 1km in length except for LVN1 (921m) and LVN2 (919m) covering all the larger areas in the de-velopment plan as then defined (Figure 7). The exact length of each transect was taken into ac-count in all subsequent analysis. Data was collected from each transect on three occasions in the period 22^nd May-9^th July 2009, this being the breeding season for most of the bird species ex-pected in the area and the time of year in which birds are normally easiest to observe given sing-ing, territorial, and warning call behaviours which are commonest at that time. Individuals were registered in a band from 0-100m north and south of the transect line. The distance to the ob-server was measured using laser binocular rangefinders, and the DISTANCE programme used to estimate detection probability at various distances (Buckland et al. 2001).

Densities of birds can then be calculated from this data using DISTANCE, though in this case (see below) densities, especially on the mountain plateau, were often too low for estimates to be calculable. All ponds and lakes on the periphery of the plan area were checked for waterfowl on every visit. Outside structured observations, all casual records of less common birds, and the lo-cation of any nests found, were noted by all members of the project team.

Figure 7. Location of transect lines for small birds and waders in the plan area for the Hitra II Wind-Power Plant. Transects were 100m in length, with the exceptions of LVN1921m) and LVN2 (919m).

2.3.1.2 Results

The number of birds of the various species observed is presented in Table 4.

Tabell 4. Total number of birds of each species observed during transect counts of the plan area for the Hitra II Wind-Power Plant.

Species Total observations

Meadow pipit / Heipiplerke 46

Wheatear/Steinskvett 25

Chaffinch/Bokfink 20

Chiffchaff/Granmeis 16

Great tit/Kjøttmeis 9

Golden plover/Heilo 8

Blackbird/Svarttrost 8

Chiffchaff/Gransanger 7

Mallard/Stokkand 6

Willow warbler/Løvsanger 5

Song thrush/Måltrost 4

Goldeneye/Kvinand 3

Redshank/Rødstilk 3

Redstart/Rødstjert 3

Twite/Bergirisk 2

Redpoll/Gråsisik 2

Dunnock/Jernspurv 2

Redwing/Rødvingetrost 2

Common sandpiper/Strandsnipe 2

Coal tit/Svartmeis 2

Willow ptarmigan/Lirype 1

Raven/Ravn 1

Woodcock/Rugde 1

Robin/Rødstrupe 1

Kestrel/Tårnfalk 1

The results indicate a clear difference in species diversity and densities between the mountain plateau on Eldsfjell (all transects except RH1-4) and in the Korsvatnet – Ramnåsheia area (RH1-4). The density of birds on the Eldsfjell plateau was low and consisted mainly of three species, meadow pipit (heipiplerke), wheatear (steinskvett), and golden plover (heilo). Willow ptarmigan and redshank were also observed. The only observations of other species in the Eldsfjell area were in or near small cliffs with scrub at the edge of the area, two twite (bergirisk) and two kes-trels (tårnfalk) (one observed outside structured observations); both possibly breeding pairs.

Casual observations of grey-headed woodpecker (gråspett) (1) and ring ouzel (ringtrost) (1) were noted outwith the tranects; the former close to the southernmost existing turbine, and the latter (an adult male) in the eastern part of Middagsvarden. A meadow pipit nest with four eggs was found ca. 10m from the base of the same turbine. To summarise, the mountain plaeau of Eldsfjel-let appears relatively impoverished both in species and in numbers of small birds and waders, which is not surprising considering the infertile underlying rock (granite), the highly exposed loca-tion, and the sparse soil coverage outwith patches of mire.

The Korsvatnet-Ramnåsheia area in the southwest lies lower than Eldsfjellet; this part of the plan area is dominated by relatively fertile mixed pine/birch woodland in natural succession, with con-siderably better developed soils than on the mountain plateau. Trees on the top of Ramnåsheia are more sparse and patchy, and the trees more bushy in form, but nevertheless support a

num-where there are patches of open mire. This area has a considerably higher density of birds, as well as a greater diversity of species. Chiffchaff (gransanger), willow warbler (løvsanger), chaf-finch (bokfink), song thrush (måltrost), redwing (rødvingtrost), blackbird (svarttrost), willow tit (granmeis), great tit (kjøttmeis), siskin (grønsisik), robin (rødstrupe), and dunnock (jernspurv) were all common. Coal tit (svartmeis), redpoll (gråsisik), redstart (rødstjert), raven (ravn), lirype (willow ptarmigan), woodcock (rugde), and common sandpiper (strandsnipe) were also observed.

Woodpeckers are difficult to register through direct observations, but marks on trees show that woodpecker species are also common. Eight grey-headed woodpeckers (gråspett) were observed outwith transect observations in woodland area on the southwest and western flanks of the Elds-fjellet massif spring-summer of 2009; further data (M. Pearson pers. comm.) shows a dense (for the species) concentration of grey-headed woodpeckers (gråspett), which are red-listed, in this area, which includes Ramnåsheia and the area adjacent to the top 265m southwest of Lauvdals-vatnet (Figure 8).

Figure 8 Relative density of grey-headed woodpecker (gråspett) in the Ramnåsheia area. Small stars indicate existing wind turbines, proposed turbines under Alternative A as squares, and under alternative B as yellow stars. Darker colours indicate increasing densities (white = area not as-sessed). Data: M. Pearson (pers. comm.).

Waterfowl are not common on lakes or ponds either in the plan area, or in the valleys between ridges of the south-western Eldsfjellet massif. A female goldeneye (kvinand) with five ducklings was seen on Lauvdalsvatnet, and a mallard (stokkand) female with five ducklings on a pond on the top of Ramnåsheia. Two female goldeneyes (kvinand) were seen on Korsvatnet. Diver

spe-cies (lomarter) did apparently not breed within or adjacent to the plan area in 2009, although a black-throated diver (storlom) was seen on Skogoddvatnet ca. 1km west of the plan area in spring, and breeding on lakes or ponds on the edge of the plan area cannot be excluded in the future. Data from Smøla (Halley & Hopshaug 2007) indicate that breeding in the wind-power plant area after construction is unlikely. The red-listed whooper swan (sangsvane) has been observed on on Skogoddvatnet and Tømmeråstjønna, ca. 2km northwest of the plan area (M. Pearson pers. comm.).